xref: /linux/net/core/sock.c (revision 6bc51cbaa9d75c7c240282da5ff270815caccac0)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		Generic socket support routines. Memory allocators, socket lock/release
7  *		handler for protocols to use and generic option handler.
8  *
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  *
85  *
86  *		This program is free software; you can redistribute it and/or
87  *		modify it under the terms of the GNU General Public License
88  *		as published by the Free Software Foundation; either version
89  *		2 of the License, or (at your option) any later version.
90  */
91 
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93 
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/errqueue.h>
97 #include <linux/types.h>
98 #include <linux/socket.h>
99 #include <linux/in.h>
100 #include <linux/kernel.h>
101 #include <linux/module.h>
102 #include <linux/proc_fs.h>
103 #include <linux/seq_file.h>
104 #include <linux/sched.h>
105 #include <linux/sched/mm.h>
106 #include <linux/timer.h>
107 #include <linux/string.h>
108 #include <linux/sockios.h>
109 #include <linux/net.h>
110 #include <linux/mm.h>
111 #include <linux/slab.h>
112 #include <linux/interrupt.h>
113 #include <linux/poll.h>
114 #include <linux/tcp.h>
115 #include <linux/init.h>
116 #include <linux/highmem.h>
117 #include <linux/user_namespace.h>
118 #include <linux/static_key.h>
119 #include <linux/memcontrol.h>
120 #include <linux/prefetch.h>
121 
122 #include <linux/uaccess.h>
123 
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <net/net_namespace.h>
128 #include <net/request_sock.h>
129 #include <net/sock.h>
130 #include <linux/net_tstamp.h>
131 #include <net/xfrm.h>
132 #include <linux/ipsec.h>
133 #include <net/cls_cgroup.h>
134 #include <net/netprio_cgroup.h>
135 #include <linux/sock_diag.h>
136 
137 #include <linux/filter.h>
138 #include <net/sock_reuseport.h>
139 
140 #include <trace/events/sock.h>
141 
142 #include <net/tcp.h>
143 #include <net/busy_poll.h>
144 
145 static DEFINE_MUTEX(proto_list_mutex);
146 static LIST_HEAD(proto_list);
147 
148 /**
149  * sk_ns_capable - General socket capability test
150  * @sk: Socket to use a capability on or through
151  * @user_ns: The user namespace of the capability to use
152  * @cap: The capability to use
153  *
154  * Test to see if the opener of the socket had when the socket was
155  * created and the current process has the capability @cap in the user
156  * namespace @user_ns.
157  */
158 bool sk_ns_capable(const struct sock *sk,
159 		   struct user_namespace *user_ns, int cap)
160 {
161 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
162 		ns_capable(user_ns, cap);
163 }
164 EXPORT_SYMBOL(sk_ns_capable);
165 
166 /**
167  * sk_capable - Socket global capability test
168  * @sk: Socket to use a capability on or through
169  * @cap: The global capability to use
170  *
171  * Test to see if the opener of the socket had when the socket was
172  * created and the current process has the capability @cap in all user
173  * namespaces.
174  */
175 bool sk_capable(const struct sock *sk, int cap)
176 {
177 	return sk_ns_capable(sk, &init_user_ns, cap);
178 }
179 EXPORT_SYMBOL(sk_capable);
180 
181 /**
182  * sk_net_capable - Network namespace socket capability test
183  * @sk: Socket to use a capability on or through
184  * @cap: The capability to use
185  *
186  * Test to see if the opener of the socket had when the socket was created
187  * and the current process has the capability @cap over the network namespace
188  * the socket is a member of.
189  */
190 bool sk_net_capable(const struct sock *sk, int cap)
191 {
192 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
193 }
194 EXPORT_SYMBOL(sk_net_capable);
195 
196 /*
197  * Each address family might have different locking rules, so we have
198  * one slock key per address family and separate keys for internal and
199  * userspace sockets.
200  */
201 static struct lock_class_key af_family_keys[AF_MAX];
202 static struct lock_class_key af_family_kern_keys[AF_MAX];
203 static struct lock_class_key af_family_slock_keys[AF_MAX];
204 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
205 
206 /*
207  * Make lock validator output more readable. (we pre-construct these
208  * strings build-time, so that runtime initialization of socket
209  * locks is fast):
210  */
211 
212 #define _sock_locks(x)						  \
213   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
214   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
215   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
216   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
217   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
218   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
219   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
220   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
221   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
222   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
223   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
224   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
225   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
226   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
227   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_MAX"
228 
229 static const char *const af_family_key_strings[AF_MAX+1] = {
230 	_sock_locks("sk_lock-")
231 };
232 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
233 	_sock_locks("slock-")
234 };
235 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
236 	_sock_locks("clock-")
237 };
238 
239 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
240 	_sock_locks("k-sk_lock-")
241 };
242 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
243 	_sock_locks("k-slock-")
244 };
245 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
246 	_sock_locks("k-clock-")
247 };
248 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
249   "rlock-AF_UNSPEC", "rlock-AF_UNIX"     , "rlock-AF_INET"     ,
250   "rlock-AF_AX25"  , "rlock-AF_IPX"      , "rlock-AF_APPLETALK",
251   "rlock-AF_NETROM", "rlock-AF_BRIDGE"   , "rlock-AF_ATMPVC"   ,
252   "rlock-AF_X25"   , "rlock-AF_INET6"    , "rlock-AF_ROSE"     ,
253   "rlock-AF_DECnet", "rlock-AF_NETBEUI"  , "rlock-AF_SECURITY" ,
254   "rlock-AF_KEY"   , "rlock-AF_NETLINK"  , "rlock-AF_PACKET"   ,
255   "rlock-AF_ASH"   , "rlock-AF_ECONET"   , "rlock-AF_ATMSVC"   ,
256   "rlock-AF_RDS"   , "rlock-AF_SNA"      , "rlock-AF_IRDA"     ,
257   "rlock-AF_PPPOX" , "rlock-AF_WANPIPE"  , "rlock-AF_LLC"      ,
258   "rlock-27"       , "rlock-28"          , "rlock-AF_CAN"      ,
259   "rlock-AF_TIPC"  , "rlock-AF_BLUETOOTH", "rlock-AF_IUCV"     ,
260   "rlock-AF_RXRPC" , "rlock-AF_ISDN"     , "rlock-AF_PHONET"   ,
261   "rlock-AF_IEEE802154", "rlock-AF_CAIF" , "rlock-AF_ALG"      ,
262   "rlock-AF_NFC"   , "rlock-AF_VSOCK"    , "rlock-AF_KCM"      ,
263   "rlock-AF_QIPCRTR", "rlock-AF_SMC"     , "rlock-AF_MAX"
264 };
265 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
266   "wlock-AF_UNSPEC", "wlock-AF_UNIX"     , "wlock-AF_INET"     ,
267   "wlock-AF_AX25"  , "wlock-AF_IPX"      , "wlock-AF_APPLETALK",
268   "wlock-AF_NETROM", "wlock-AF_BRIDGE"   , "wlock-AF_ATMPVC"   ,
269   "wlock-AF_X25"   , "wlock-AF_INET6"    , "wlock-AF_ROSE"     ,
270   "wlock-AF_DECnet", "wlock-AF_NETBEUI"  , "wlock-AF_SECURITY" ,
271   "wlock-AF_KEY"   , "wlock-AF_NETLINK"  , "wlock-AF_PACKET"   ,
272   "wlock-AF_ASH"   , "wlock-AF_ECONET"   , "wlock-AF_ATMSVC"   ,
273   "wlock-AF_RDS"   , "wlock-AF_SNA"      , "wlock-AF_IRDA"     ,
274   "wlock-AF_PPPOX" , "wlock-AF_WANPIPE"  , "wlock-AF_LLC"      ,
275   "wlock-27"       , "wlock-28"          , "wlock-AF_CAN"      ,
276   "wlock-AF_TIPC"  , "wlock-AF_BLUETOOTH", "wlock-AF_IUCV"     ,
277   "wlock-AF_RXRPC" , "wlock-AF_ISDN"     , "wlock-AF_PHONET"   ,
278   "wlock-AF_IEEE802154", "wlock-AF_CAIF" , "wlock-AF_ALG"      ,
279   "wlock-AF_NFC"   , "wlock-AF_VSOCK"    , "wlock-AF_KCM"      ,
280   "wlock-AF_QIPCRTR", "wlock-AF_SMC"     , "wlock-AF_MAX"
281 };
282 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
283   "elock-AF_UNSPEC", "elock-AF_UNIX"     , "elock-AF_INET"     ,
284   "elock-AF_AX25"  , "elock-AF_IPX"      , "elock-AF_APPLETALK",
285   "elock-AF_NETROM", "elock-AF_BRIDGE"   , "elock-AF_ATMPVC"   ,
286   "elock-AF_X25"   , "elock-AF_INET6"    , "elock-AF_ROSE"     ,
287   "elock-AF_DECnet", "elock-AF_NETBEUI"  , "elock-AF_SECURITY" ,
288   "elock-AF_KEY"   , "elock-AF_NETLINK"  , "elock-AF_PACKET"   ,
289   "elock-AF_ASH"   , "elock-AF_ECONET"   , "elock-AF_ATMSVC"   ,
290   "elock-AF_RDS"   , "elock-AF_SNA"      , "elock-AF_IRDA"     ,
291   "elock-AF_PPPOX" , "elock-AF_WANPIPE"  , "elock-AF_LLC"      ,
292   "elock-27"       , "elock-28"          , "elock-AF_CAN"      ,
293   "elock-AF_TIPC"  , "elock-AF_BLUETOOTH", "elock-AF_IUCV"     ,
294   "elock-AF_RXRPC" , "elock-AF_ISDN"     , "elock-AF_PHONET"   ,
295   "elock-AF_IEEE802154", "elock-AF_CAIF" , "elock-AF_ALG"      ,
296   "elock-AF_NFC"   , "elock-AF_VSOCK"    , "elock-AF_KCM"      ,
297   "elock-AF_QIPCRTR", "elock-AF_SMC"     , "elock-AF_MAX"
298 };
299 
300 /*
301  * sk_callback_lock and sk queues locking rules are per-address-family,
302  * so split the lock classes by using a per-AF key:
303  */
304 static struct lock_class_key af_callback_keys[AF_MAX];
305 static struct lock_class_key af_rlock_keys[AF_MAX];
306 static struct lock_class_key af_wlock_keys[AF_MAX];
307 static struct lock_class_key af_elock_keys[AF_MAX];
308 static struct lock_class_key af_kern_callback_keys[AF_MAX];
309 
310 /* Take into consideration the size of the struct sk_buff overhead in the
311  * determination of these values, since that is non-constant across
312  * platforms.  This makes socket queueing behavior and performance
313  * not depend upon such differences.
314  */
315 #define _SK_MEM_PACKETS		256
316 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
317 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
318 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
319 
320 /* Run time adjustable parameters. */
321 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
322 EXPORT_SYMBOL(sysctl_wmem_max);
323 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
324 EXPORT_SYMBOL(sysctl_rmem_max);
325 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
326 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
327 
328 /* Maximal space eaten by iovec or ancillary data plus some space */
329 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
330 EXPORT_SYMBOL(sysctl_optmem_max);
331 
332 int sysctl_tstamp_allow_data __read_mostly = 1;
333 
334 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
335 EXPORT_SYMBOL_GPL(memalloc_socks);
336 
337 /**
338  * sk_set_memalloc - sets %SOCK_MEMALLOC
339  * @sk: socket to set it on
340  *
341  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
342  * It's the responsibility of the admin to adjust min_free_kbytes
343  * to meet the requirements
344  */
345 void sk_set_memalloc(struct sock *sk)
346 {
347 	sock_set_flag(sk, SOCK_MEMALLOC);
348 	sk->sk_allocation |= __GFP_MEMALLOC;
349 	static_key_slow_inc(&memalloc_socks);
350 }
351 EXPORT_SYMBOL_GPL(sk_set_memalloc);
352 
353 void sk_clear_memalloc(struct sock *sk)
354 {
355 	sock_reset_flag(sk, SOCK_MEMALLOC);
356 	sk->sk_allocation &= ~__GFP_MEMALLOC;
357 	static_key_slow_dec(&memalloc_socks);
358 
359 	/*
360 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
361 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
362 	 * it has rmem allocations due to the last swapfile being deactivated
363 	 * but there is a risk that the socket is unusable due to exceeding
364 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
365 	 */
366 	sk_mem_reclaim(sk);
367 }
368 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
369 
370 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
371 {
372 	int ret;
373 	unsigned int noreclaim_flag;
374 
375 	/* these should have been dropped before queueing */
376 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
377 
378 	noreclaim_flag = memalloc_noreclaim_save();
379 	ret = sk->sk_backlog_rcv(sk, skb);
380 	memalloc_noreclaim_restore(noreclaim_flag);
381 
382 	return ret;
383 }
384 EXPORT_SYMBOL(__sk_backlog_rcv);
385 
386 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
387 {
388 	struct timeval tv;
389 
390 	if (optlen < sizeof(tv))
391 		return -EINVAL;
392 	if (copy_from_user(&tv, optval, sizeof(tv)))
393 		return -EFAULT;
394 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
395 		return -EDOM;
396 
397 	if (tv.tv_sec < 0) {
398 		static int warned __read_mostly;
399 
400 		*timeo_p = 0;
401 		if (warned < 10 && net_ratelimit()) {
402 			warned++;
403 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
404 				__func__, current->comm, task_pid_nr(current));
405 		}
406 		return 0;
407 	}
408 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
409 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
410 		return 0;
411 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
412 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ);
413 	return 0;
414 }
415 
416 static void sock_warn_obsolete_bsdism(const char *name)
417 {
418 	static int warned;
419 	static char warncomm[TASK_COMM_LEN];
420 	if (strcmp(warncomm, current->comm) && warned < 5) {
421 		strcpy(warncomm,  current->comm);
422 		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
423 			warncomm, name);
424 		warned++;
425 	}
426 }
427 
428 static bool sock_needs_netstamp(const struct sock *sk)
429 {
430 	switch (sk->sk_family) {
431 	case AF_UNSPEC:
432 	case AF_UNIX:
433 		return false;
434 	default:
435 		return true;
436 	}
437 }
438 
439 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
440 {
441 	if (sk->sk_flags & flags) {
442 		sk->sk_flags &= ~flags;
443 		if (sock_needs_netstamp(sk) &&
444 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
445 			net_disable_timestamp();
446 	}
447 }
448 
449 
450 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
451 {
452 	unsigned long flags;
453 	struct sk_buff_head *list = &sk->sk_receive_queue;
454 
455 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
456 		atomic_inc(&sk->sk_drops);
457 		trace_sock_rcvqueue_full(sk, skb);
458 		return -ENOMEM;
459 	}
460 
461 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
462 		atomic_inc(&sk->sk_drops);
463 		return -ENOBUFS;
464 	}
465 
466 	skb->dev = NULL;
467 	skb_set_owner_r(skb, sk);
468 
469 	/* we escape from rcu protected region, make sure we dont leak
470 	 * a norefcounted dst
471 	 */
472 	skb_dst_force(skb);
473 
474 	spin_lock_irqsave(&list->lock, flags);
475 	sock_skb_set_dropcount(sk, skb);
476 	__skb_queue_tail(list, skb);
477 	spin_unlock_irqrestore(&list->lock, flags);
478 
479 	if (!sock_flag(sk, SOCK_DEAD))
480 		sk->sk_data_ready(sk);
481 	return 0;
482 }
483 EXPORT_SYMBOL(__sock_queue_rcv_skb);
484 
485 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
486 {
487 	int err;
488 
489 	err = sk_filter(sk, skb);
490 	if (err)
491 		return err;
492 
493 	return __sock_queue_rcv_skb(sk, skb);
494 }
495 EXPORT_SYMBOL(sock_queue_rcv_skb);
496 
497 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
498 		     const int nested, unsigned int trim_cap, bool refcounted)
499 {
500 	int rc = NET_RX_SUCCESS;
501 
502 	if (sk_filter_trim_cap(sk, skb, trim_cap))
503 		goto discard_and_relse;
504 
505 	skb->dev = NULL;
506 
507 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
508 		atomic_inc(&sk->sk_drops);
509 		goto discard_and_relse;
510 	}
511 	if (nested)
512 		bh_lock_sock_nested(sk);
513 	else
514 		bh_lock_sock(sk);
515 	if (!sock_owned_by_user(sk)) {
516 		/*
517 		 * trylock + unlock semantics:
518 		 */
519 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
520 
521 		rc = sk_backlog_rcv(sk, skb);
522 
523 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
524 	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
525 		bh_unlock_sock(sk);
526 		atomic_inc(&sk->sk_drops);
527 		goto discard_and_relse;
528 	}
529 
530 	bh_unlock_sock(sk);
531 out:
532 	if (refcounted)
533 		sock_put(sk);
534 	return rc;
535 discard_and_relse:
536 	kfree_skb(skb);
537 	goto out;
538 }
539 EXPORT_SYMBOL(__sk_receive_skb);
540 
541 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
542 {
543 	struct dst_entry *dst = __sk_dst_get(sk);
544 
545 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
546 		sk_tx_queue_clear(sk);
547 		sk->sk_dst_pending_confirm = 0;
548 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
549 		dst_release(dst);
550 		return NULL;
551 	}
552 
553 	return dst;
554 }
555 EXPORT_SYMBOL(__sk_dst_check);
556 
557 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
558 {
559 	struct dst_entry *dst = sk_dst_get(sk);
560 
561 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
562 		sk_dst_reset(sk);
563 		dst_release(dst);
564 		return NULL;
565 	}
566 
567 	return dst;
568 }
569 EXPORT_SYMBOL(sk_dst_check);
570 
571 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
572 				int optlen)
573 {
574 	int ret = -ENOPROTOOPT;
575 #ifdef CONFIG_NETDEVICES
576 	struct net *net = sock_net(sk);
577 	char devname[IFNAMSIZ];
578 	int index;
579 
580 	/* Sorry... */
581 	ret = -EPERM;
582 	if (!ns_capable(net->user_ns, CAP_NET_RAW))
583 		goto out;
584 
585 	ret = -EINVAL;
586 	if (optlen < 0)
587 		goto out;
588 
589 	/* Bind this socket to a particular device like "eth0",
590 	 * as specified in the passed interface name. If the
591 	 * name is "" or the option length is zero the socket
592 	 * is not bound.
593 	 */
594 	if (optlen > IFNAMSIZ - 1)
595 		optlen = IFNAMSIZ - 1;
596 	memset(devname, 0, sizeof(devname));
597 
598 	ret = -EFAULT;
599 	if (copy_from_user(devname, optval, optlen))
600 		goto out;
601 
602 	index = 0;
603 	if (devname[0] != '\0') {
604 		struct net_device *dev;
605 
606 		rcu_read_lock();
607 		dev = dev_get_by_name_rcu(net, devname);
608 		if (dev)
609 			index = dev->ifindex;
610 		rcu_read_unlock();
611 		ret = -ENODEV;
612 		if (!dev)
613 			goto out;
614 	}
615 
616 	lock_sock(sk);
617 	sk->sk_bound_dev_if = index;
618 	sk_dst_reset(sk);
619 	release_sock(sk);
620 
621 	ret = 0;
622 
623 out:
624 #endif
625 
626 	return ret;
627 }
628 
629 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
630 				int __user *optlen, int len)
631 {
632 	int ret = -ENOPROTOOPT;
633 #ifdef CONFIG_NETDEVICES
634 	struct net *net = sock_net(sk);
635 	char devname[IFNAMSIZ];
636 
637 	if (sk->sk_bound_dev_if == 0) {
638 		len = 0;
639 		goto zero;
640 	}
641 
642 	ret = -EINVAL;
643 	if (len < IFNAMSIZ)
644 		goto out;
645 
646 	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
647 	if (ret)
648 		goto out;
649 
650 	len = strlen(devname) + 1;
651 
652 	ret = -EFAULT;
653 	if (copy_to_user(optval, devname, len))
654 		goto out;
655 
656 zero:
657 	ret = -EFAULT;
658 	if (put_user(len, optlen))
659 		goto out;
660 
661 	ret = 0;
662 
663 out:
664 #endif
665 
666 	return ret;
667 }
668 
669 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
670 {
671 	if (valbool)
672 		sock_set_flag(sk, bit);
673 	else
674 		sock_reset_flag(sk, bit);
675 }
676 
677 bool sk_mc_loop(struct sock *sk)
678 {
679 	if (dev_recursion_level())
680 		return false;
681 	if (!sk)
682 		return true;
683 	switch (sk->sk_family) {
684 	case AF_INET:
685 		return inet_sk(sk)->mc_loop;
686 #if IS_ENABLED(CONFIG_IPV6)
687 	case AF_INET6:
688 		return inet6_sk(sk)->mc_loop;
689 #endif
690 	}
691 	WARN_ON(1);
692 	return true;
693 }
694 EXPORT_SYMBOL(sk_mc_loop);
695 
696 /*
697  *	This is meant for all protocols to use and covers goings on
698  *	at the socket level. Everything here is generic.
699  */
700 
701 int sock_setsockopt(struct socket *sock, int level, int optname,
702 		    char __user *optval, unsigned int optlen)
703 {
704 	struct sock *sk = sock->sk;
705 	int val;
706 	int valbool;
707 	struct linger ling;
708 	int ret = 0;
709 
710 	/*
711 	 *	Options without arguments
712 	 */
713 
714 	if (optname == SO_BINDTODEVICE)
715 		return sock_setbindtodevice(sk, optval, optlen);
716 
717 	if (optlen < sizeof(int))
718 		return -EINVAL;
719 
720 	if (get_user(val, (int __user *)optval))
721 		return -EFAULT;
722 
723 	valbool = val ? 1 : 0;
724 
725 	lock_sock(sk);
726 
727 	switch (optname) {
728 	case SO_DEBUG:
729 		if (val && !capable(CAP_NET_ADMIN))
730 			ret = -EACCES;
731 		else
732 			sock_valbool_flag(sk, SOCK_DBG, valbool);
733 		break;
734 	case SO_REUSEADDR:
735 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
736 		break;
737 	case SO_REUSEPORT:
738 		sk->sk_reuseport = valbool;
739 		break;
740 	case SO_TYPE:
741 	case SO_PROTOCOL:
742 	case SO_DOMAIN:
743 	case SO_ERROR:
744 		ret = -ENOPROTOOPT;
745 		break;
746 	case SO_DONTROUTE:
747 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
748 		break;
749 	case SO_BROADCAST:
750 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
751 		break;
752 	case SO_SNDBUF:
753 		/* Don't error on this BSD doesn't and if you think
754 		 * about it this is right. Otherwise apps have to
755 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
756 		 * are treated in BSD as hints
757 		 */
758 		val = min_t(u32, val, sysctl_wmem_max);
759 set_sndbuf:
760 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
761 		sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
762 		/* Wake up sending tasks if we upped the value. */
763 		sk->sk_write_space(sk);
764 		break;
765 
766 	case SO_SNDBUFFORCE:
767 		if (!capable(CAP_NET_ADMIN)) {
768 			ret = -EPERM;
769 			break;
770 		}
771 		goto set_sndbuf;
772 
773 	case SO_RCVBUF:
774 		/* Don't error on this BSD doesn't and if you think
775 		 * about it this is right. Otherwise apps have to
776 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
777 		 * are treated in BSD as hints
778 		 */
779 		val = min_t(u32, val, sysctl_rmem_max);
780 set_rcvbuf:
781 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
782 		/*
783 		 * We double it on the way in to account for
784 		 * "struct sk_buff" etc. overhead.   Applications
785 		 * assume that the SO_RCVBUF setting they make will
786 		 * allow that much actual data to be received on that
787 		 * socket.
788 		 *
789 		 * Applications are unaware that "struct sk_buff" and
790 		 * other overheads allocate from the receive buffer
791 		 * during socket buffer allocation.
792 		 *
793 		 * And after considering the possible alternatives,
794 		 * returning the value we actually used in getsockopt
795 		 * is the most desirable behavior.
796 		 */
797 		sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
798 		break;
799 
800 	case SO_RCVBUFFORCE:
801 		if (!capable(CAP_NET_ADMIN)) {
802 			ret = -EPERM;
803 			break;
804 		}
805 		goto set_rcvbuf;
806 
807 	case SO_KEEPALIVE:
808 		if (sk->sk_prot->keepalive)
809 			sk->sk_prot->keepalive(sk, valbool);
810 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
811 		break;
812 
813 	case SO_OOBINLINE:
814 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
815 		break;
816 
817 	case SO_NO_CHECK:
818 		sk->sk_no_check_tx = valbool;
819 		break;
820 
821 	case SO_PRIORITY:
822 		if ((val >= 0 && val <= 6) ||
823 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
824 			sk->sk_priority = val;
825 		else
826 			ret = -EPERM;
827 		break;
828 
829 	case SO_LINGER:
830 		if (optlen < sizeof(ling)) {
831 			ret = -EINVAL;	/* 1003.1g */
832 			break;
833 		}
834 		if (copy_from_user(&ling, optval, sizeof(ling))) {
835 			ret = -EFAULT;
836 			break;
837 		}
838 		if (!ling.l_onoff)
839 			sock_reset_flag(sk, SOCK_LINGER);
840 		else {
841 #if (BITS_PER_LONG == 32)
842 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
843 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
844 			else
845 #endif
846 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
847 			sock_set_flag(sk, SOCK_LINGER);
848 		}
849 		break;
850 
851 	case SO_BSDCOMPAT:
852 		sock_warn_obsolete_bsdism("setsockopt");
853 		break;
854 
855 	case SO_PASSCRED:
856 		if (valbool)
857 			set_bit(SOCK_PASSCRED, &sock->flags);
858 		else
859 			clear_bit(SOCK_PASSCRED, &sock->flags);
860 		break;
861 
862 	case SO_TIMESTAMP:
863 	case SO_TIMESTAMPNS:
864 		if (valbool)  {
865 			if (optname == SO_TIMESTAMP)
866 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
867 			else
868 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
869 			sock_set_flag(sk, SOCK_RCVTSTAMP);
870 			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
871 		} else {
872 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
873 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
874 		}
875 		break;
876 
877 	case SO_TIMESTAMPING:
878 		if (val & ~SOF_TIMESTAMPING_MASK) {
879 			ret = -EINVAL;
880 			break;
881 		}
882 
883 		if (val & SOF_TIMESTAMPING_OPT_ID &&
884 		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
885 			if (sk->sk_protocol == IPPROTO_TCP &&
886 			    sk->sk_type == SOCK_STREAM) {
887 				if ((1 << sk->sk_state) &
888 				    (TCPF_CLOSE | TCPF_LISTEN)) {
889 					ret = -EINVAL;
890 					break;
891 				}
892 				sk->sk_tskey = tcp_sk(sk)->snd_una;
893 			} else {
894 				sk->sk_tskey = 0;
895 			}
896 		}
897 
898 		if (val & SOF_TIMESTAMPING_OPT_STATS &&
899 		    !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
900 			ret = -EINVAL;
901 			break;
902 		}
903 
904 		sk->sk_tsflags = val;
905 		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
906 			sock_enable_timestamp(sk,
907 					      SOCK_TIMESTAMPING_RX_SOFTWARE);
908 		else
909 			sock_disable_timestamp(sk,
910 					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
911 		break;
912 
913 	case SO_RCVLOWAT:
914 		if (val < 0)
915 			val = INT_MAX;
916 		sk->sk_rcvlowat = val ? : 1;
917 		break;
918 
919 	case SO_RCVTIMEO:
920 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
921 		break;
922 
923 	case SO_SNDTIMEO:
924 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
925 		break;
926 
927 	case SO_ATTACH_FILTER:
928 		ret = -EINVAL;
929 		if (optlen == sizeof(struct sock_fprog)) {
930 			struct sock_fprog fprog;
931 
932 			ret = -EFAULT;
933 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
934 				break;
935 
936 			ret = sk_attach_filter(&fprog, sk);
937 		}
938 		break;
939 
940 	case SO_ATTACH_BPF:
941 		ret = -EINVAL;
942 		if (optlen == sizeof(u32)) {
943 			u32 ufd;
944 
945 			ret = -EFAULT;
946 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
947 				break;
948 
949 			ret = sk_attach_bpf(ufd, sk);
950 		}
951 		break;
952 
953 	case SO_ATTACH_REUSEPORT_CBPF:
954 		ret = -EINVAL;
955 		if (optlen == sizeof(struct sock_fprog)) {
956 			struct sock_fprog fprog;
957 
958 			ret = -EFAULT;
959 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
960 				break;
961 
962 			ret = sk_reuseport_attach_filter(&fprog, sk);
963 		}
964 		break;
965 
966 	case SO_ATTACH_REUSEPORT_EBPF:
967 		ret = -EINVAL;
968 		if (optlen == sizeof(u32)) {
969 			u32 ufd;
970 
971 			ret = -EFAULT;
972 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
973 				break;
974 
975 			ret = sk_reuseport_attach_bpf(ufd, sk);
976 		}
977 		break;
978 
979 	case SO_DETACH_FILTER:
980 		ret = sk_detach_filter(sk);
981 		break;
982 
983 	case SO_LOCK_FILTER:
984 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
985 			ret = -EPERM;
986 		else
987 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
988 		break;
989 
990 	case SO_PASSSEC:
991 		if (valbool)
992 			set_bit(SOCK_PASSSEC, &sock->flags);
993 		else
994 			clear_bit(SOCK_PASSSEC, &sock->flags);
995 		break;
996 	case SO_MARK:
997 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
998 			ret = -EPERM;
999 		else
1000 			sk->sk_mark = val;
1001 		break;
1002 
1003 	case SO_RXQ_OVFL:
1004 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1005 		break;
1006 
1007 	case SO_WIFI_STATUS:
1008 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1009 		break;
1010 
1011 	case SO_PEEK_OFF:
1012 		if (sock->ops->set_peek_off)
1013 			ret = sock->ops->set_peek_off(sk, val);
1014 		else
1015 			ret = -EOPNOTSUPP;
1016 		break;
1017 
1018 	case SO_NOFCS:
1019 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1020 		break;
1021 
1022 	case SO_SELECT_ERR_QUEUE:
1023 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1024 		break;
1025 
1026 #ifdef CONFIG_NET_RX_BUSY_POLL
1027 	case SO_BUSY_POLL:
1028 		/* allow unprivileged users to decrease the value */
1029 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1030 			ret = -EPERM;
1031 		else {
1032 			if (val < 0)
1033 				ret = -EINVAL;
1034 			else
1035 				sk->sk_ll_usec = val;
1036 		}
1037 		break;
1038 #endif
1039 
1040 	case SO_MAX_PACING_RATE:
1041 		sk->sk_max_pacing_rate = val;
1042 		sk->sk_pacing_rate = min(sk->sk_pacing_rate,
1043 					 sk->sk_max_pacing_rate);
1044 		break;
1045 
1046 	case SO_INCOMING_CPU:
1047 		sk->sk_incoming_cpu = val;
1048 		break;
1049 
1050 	case SO_CNX_ADVICE:
1051 		if (val == 1)
1052 			dst_negative_advice(sk);
1053 		break;
1054 	default:
1055 		ret = -ENOPROTOOPT;
1056 		break;
1057 	}
1058 	release_sock(sk);
1059 	return ret;
1060 }
1061 EXPORT_SYMBOL(sock_setsockopt);
1062 
1063 
1064 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1065 			  struct ucred *ucred)
1066 {
1067 	ucred->pid = pid_vnr(pid);
1068 	ucred->uid = ucred->gid = -1;
1069 	if (cred) {
1070 		struct user_namespace *current_ns = current_user_ns();
1071 
1072 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1073 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1074 	}
1075 }
1076 
1077 int sock_getsockopt(struct socket *sock, int level, int optname,
1078 		    char __user *optval, int __user *optlen)
1079 {
1080 	struct sock *sk = sock->sk;
1081 
1082 	union {
1083 		int val;
1084 		u64 val64;
1085 		struct linger ling;
1086 		struct timeval tm;
1087 	} v;
1088 
1089 	int lv = sizeof(int);
1090 	int len;
1091 
1092 	if (get_user(len, optlen))
1093 		return -EFAULT;
1094 	if (len < 0)
1095 		return -EINVAL;
1096 
1097 	memset(&v, 0, sizeof(v));
1098 
1099 	switch (optname) {
1100 	case SO_DEBUG:
1101 		v.val = sock_flag(sk, SOCK_DBG);
1102 		break;
1103 
1104 	case SO_DONTROUTE:
1105 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1106 		break;
1107 
1108 	case SO_BROADCAST:
1109 		v.val = sock_flag(sk, SOCK_BROADCAST);
1110 		break;
1111 
1112 	case SO_SNDBUF:
1113 		v.val = sk->sk_sndbuf;
1114 		break;
1115 
1116 	case SO_RCVBUF:
1117 		v.val = sk->sk_rcvbuf;
1118 		break;
1119 
1120 	case SO_REUSEADDR:
1121 		v.val = sk->sk_reuse;
1122 		break;
1123 
1124 	case SO_REUSEPORT:
1125 		v.val = sk->sk_reuseport;
1126 		break;
1127 
1128 	case SO_KEEPALIVE:
1129 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1130 		break;
1131 
1132 	case SO_TYPE:
1133 		v.val = sk->sk_type;
1134 		break;
1135 
1136 	case SO_PROTOCOL:
1137 		v.val = sk->sk_protocol;
1138 		break;
1139 
1140 	case SO_DOMAIN:
1141 		v.val = sk->sk_family;
1142 		break;
1143 
1144 	case SO_ERROR:
1145 		v.val = -sock_error(sk);
1146 		if (v.val == 0)
1147 			v.val = xchg(&sk->sk_err_soft, 0);
1148 		break;
1149 
1150 	case SO_OOBINLINE:
1151 		v.val = sock_flag(sk, SOCK_URGINLINE);
1152 		break;
1153 
1154 	case SO_NO_CHECK:
1155 		v.val = sk->sk_no_check_tx;
1156 		break;
1157 
1158 	case SO_PRIORITY:
1159 		v.val = sk->sk_priority;
1160 		break;
1161 
1162 	case SO_LINGER:
1163 		lv		= sizeof(v.ling);
1164 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1165 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1166 		break;
1167 
1168 	case SO_BSDCOMPAT:
1169 		sock_warn_obsolete_bsdism("getsockopt");
1170 		break;
1171 
1172 	case SO_TIMESTAMP:
1173 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1174 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1175 		break;
1176 
1177 	case SO_TIMESTAMPNS:
1178 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1179 		break;
1180 
1181 	case SO_TIMESTAMPING:
1182 		v.val = sk->sk_tsflags;
1183 		break;
1184 
1185 	case SO_RCVTIMEO:
1186 		lv = sizeof(struct timeval);
1187 		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1188 			v.tm.tv_sec = 0;
1189 			v.tm.tv_usec = 0;
1190 		} else {
1191 			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1192 			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
1193 		}
1194 		break;
1195 
1196 	case SO_SNDTIMEO:
1197 		lv = sizeof(struct timeval);
1198 		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1199 			v.tm.tv_sec = 0;
1200 			v.tm.tv_usec = 0;
1201 		} else {
1202 			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1203 			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1204 		}
1205 		break;
1206 
1207 	case SO_RCVLOWAT:
1208 		v.val = sk->sk_rcvlowat;
1209 		break;
1210 
1211 	case SO_SNDLOWAT:
1212 		v.val = 1;
1213 		break;
1214 
1215 	case SO_PASSCRED:
1216 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1217 		break;
1218 
1219 	case SO_PEERCRED:
1220 	{
1221 		struct ucred peercred;
1222 		if (len > sizeof(peercred))
1223 			len = sizeof(peercred);
1224 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1225 		if (copy_to_user(optval, &peercred, len))
1226 			return -EFAULT;
1227 		goto lenout;
1228 	}
1229 
1230 	case SO_PEERNAME:
1231 	{
1232 		char address[128];
1233 
1234 		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1235 			return -ENOTCONN;
1236 		if (lv < len)
1237 			return -EINVAL;
1238 		if (copy_to_user(optval, address, len))
1239 			return -EFAULT;
1240 		goto lenout;
1241 	}
1242 
1243 	/* Dubious BSD thing... Probably nobody even uses it, but
1244 	 * the UNIX standard wants it for whatever reason... -DaveM
1245 	 */
1246 	case SO_ACCEPTCONN:
1247 		v.val = sk->sk_state == TCP_LISTEN;
1248 		break;
1249 
1250 	case SO_PASSSEC:
1251 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1252 		break;
1253 
1254 	case SO_PEERSEC:
1255 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1256 
1257 	case SO_MARK:
1258 		v.val = sk->sk_mark;
1259 		break;
1260 
1261 	case SO_RXQ_OVFL:
1262 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1263 		break;
1264 
1265 	case SO_WIFI_STATUS:
1266 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1267 		break;
1268 
1269 	case SO_PEEK_OFF:
1270 		if (!sock->ops->set_peek_off)
1271 			return -EOPNOTSUPP;
1272 
1273 		v.val = sk->sk_peek_off;
1274 		break;
1275 	case SO_NOFCS:
1276 		v.val = sock_flag(sk, SOCK_NOFCS);
1277 		break;
1278 
1279 	case SO_BINDTODEVICE:
1280 		return sock_getbindtodevice(sk, optval, optlen, len);
1281 
1282 	case SO_GET_FILTER:
1283 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1284 		if (len < 0)
1285 			return len;
1286 
1287 		goto lenout;
1288 
1289 	case SO_LOCK_FILTER:
1290 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1291 		break;
1292 
1293 	case SO_BPF_EXTENSIONS:
1294 		v.val = bpf_tell_extensions();
1295 		break;
1296 
1297 	case SO_SELECT_ERR_QUEUE:
1298 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1299 		break;
1300 
1301 #ifdef CONFIG_NET_RX_BUSY_POLL
1302 	case SO_BUSY_POLL:
1303 		v.val = sk->sk_ll_usec;
1304 		break;
1305 #endif
1306 
1307 	case SO_MAX_PACING_RATE:
1308 		v.val = sk->sk_max_pacing_rate;
1309 		break;
1310 
1311 	case SO_INCOMING_CPU:
1312 		v.val = sk->sk_incoming_cpu;
1313 		break;
1314 
1315 	case SO_MEMINFO:
1316 	{
1317 		u32 meminfo[SK_MEMINFO_VARS];
1318 
1319 		if (get_user(len, optlen))
1320 			return -EFAULT;
1321 
1322 		sk_get_meminfo(sk, meminfo);
1323 
1324 		len = min_t(unsigned int, len, sizeof(meminfo));
1325 		if (copy_to_user(optval, &meminfo, len))
1326 			return -EFAULT;
1327 
1328 		goto lenout;
1329 	}
1330 
1331 #ifdef CONFIG_NET_RX_BUSY_POLL
1332 	case SO_INCOMING_NAPI_ID:
1333 		v.val = READ_ONCE(sk->sk_napi_id);
1334 
1335 		/* aggregate non-NAPI IDs down to 0 */
1336 		if (v.val < MIN_NAPI_ID)
1337 			v.val = 0;
1338 
1339 		break;
1340 #endif
1341 
1342 	case SO_COOKIE:
1343 		lv = sizeof(u64);
1344 		if (len < lv)
1345 			return -EINVAL;
1346 		v.val64 = sock_gen_cookie(sk);
1347 		break;
1348 
1349 	default:
1350 		/* We implement the SO_SNDLOWAT etc to not be settable
1351 		 * (1003.1g 7).
1352 		 */
1353 		return -ENOPROTOOPT;
1354 	}
1355 
1356 	if (len > lv)
1357 		len = lv;
1358 	if (copy_to_user(optval, &v, len))
1359 		return -EFAULT;
1360 lenout:
1361 	if (put_user(len, optlen))
1362 		return -EFAULT;
1363 	return 0;
1364 }
1365 
1366 /*
1367  * Initialize an sk_lock.
1368  *
1369  * (We also register the sk_lock with the lock validator.)
1370  */
1371 static inline void sock_lock_init(struct sock *sk)
1372 {
1373 	if (sk->sk_kern_sock)
1374 		sock_lock_init_class_and_name(
1375 			sk,
1376 			af_family_kern_slock_key_strings[sk->sk_family],
1377 			af_family_kern_slock_keys + sk->sk_family,
1378 			af_family_kern_key_strings[sk->sk_family],
1379 			af_family_kern_keys + sk->sk_family);
1380 	else
1381 		sock_lock_init_class_and_name(
1382 			sk,
1383 			af_family_slock_key_strings[sk->sk_family],
1384 			af_family_slock_keys + sk->sk_family,
1385 			af_family_key_strings[sk->sk_family],
1386 			af_family_keys + sk->sk_family);
1387 }
1388 
1389 /*
1390  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1391  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1392  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1393  */
1394 static void sock_copy(struct sock *nsk, const struct sock *osk)
1395 {
1396 #ifdef CONFIG_SECURITY_NETWORK
1397 	void *sptr = nsk->sk_security;
1398 #endif
1399 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1400 
1401 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1402 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1403 
1404 #ifdef CONFIG_SECURITY_NETWORK
1405 	nsk->sk_security = sptr;
1406 	security_sk_clone(osk, nsk);
1407 #endif
1408 }
1409 
1410 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1411 		int family)
1412 {
1413 	struct sock *sk;
1414 	struct kmem_cache *slab;
1415 
1416 	slab = prot->slab;
1417 	if (slab != NULL) {
1418 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1419 		if (!sk)
1420 			return sk;
1421 		if (priority & __GFP_ZERO)
1422 			sk_prot_clear_nulls(sk, prot->obj_size);
1423 	} else
1424 		sk = kmalloc(prot->obj_size, priority);
1425 
1426 	if (sk != NULL) {
1427 		kmemcheck_annotate_bitfield(sk, flags);
1428 
1429 		if (security_sk_alloc(sk, family, priority))
1430 			goto out_free;
1431 
1432 		if (!try_module_get(prot->owner))
1433 			goto out_free_sec;
1434 		sk_tx_queue_clear(sk);
1435 	}
1436 
1437 	return sk;
1438 
1439 out_free_sec:
1440 	security_sk_free(sk);
1441 out_free:
1442 	if (slab != NULL)
1443 		kmem_cache_free(slab, sk);
1444 	else
1445 		kfree(sk);
1446 	return NULL;
1447 }
1448 
1449 static void sk_prot_free(struct proto *prot, struct sock *sk)
1450 {
1451 	struct kmem_cache *slab;
1452 	struct module *owner;
1453 
1454 	owner = prot->owner;
1455 	slab = prot->slab;
1456 
1457 	cgroup_sk_free(&sk->sk_cgrp_data);
1458 	mem_cgroup_sk_free(sk);
1459 	security_sk_free(sk);
1460 	if (slab != NULL)
1461 		kmem_cache_free(slab, sk);
1462 	else
1463 		kfree(sk);
1464 	module_put(owner);
1465 }
1466 
1467 /**
1468  *	sk_alloc - All socket objects are allocated here
1469  *	@net: the applicable net namespace
1470  *	@family: protocol family
1471  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1472  *	@prot: struct proto associated with this new sock instance
1473  *	@kern: is this to be a kernel socket?
1474  */
1475 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1476 		      struct proto *prot, int kern)
1477 {
1478 	struct sock *sk;
1479 
1480 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1481 	if (sk) {
1482 		sk->sk_family = family;
1483 		/*
1484 		 * See comment in struct sock definition to understand
1485 		 * why we need sk_prot_creator -acme
1486 		 */
1487 		sk->sk_prot = sk->sk_prot_creator = prot;
1488 		sk->sk_kern_sock = kern;
1489 		sock_lock_init(sk);
1490 		sk->sk_net_refcnt = kern ? 0 : 1;
1491 		if (likely(sk->sk_net_refcnt))
1492 			get_net(net);
1493 		sock_net_set(sk, net);
1494 		atomic_set(&sk->sk_wmem_alloc, 1);
1495 
1496 		mem_cgroup_sk_alloc(sk);
1497 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1498 		sock_update_classid(&sk->sk_cgrp_data);
1499 		sock_update_netprioidx(&sk->sk_cgrp_data);
1500 	}
1501 
1502 	return sk;
1503 }
1504 EXPORT_SYMBOL(sk_alloc);
1505 
1506 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1507  * grace period. This is the case for UDP sockets and TCP listeners.
1508  */
1509 static void __sk_destruct(struct rcu_head *head)
1510 {
1511 	struct sock *sk = container_of(head, struct sock, sk_rcu);
1512 	struct sk_filter *filter;
1513 
1514 	if (sk->sk_destruct)
1515 		sk->sk_destruct(sk);
1516 
1517 	filter = rcu_dereference_check(sk->sk_filter,
1518 				       atomic_read(&sk->sk_wmem_alloc) == 0);
1519 	if (filter) {
1520 		sk_filter_uncharge(sk, filter);
1521 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1522 	}
1523 	if (rcu_access_pointer(sk->sk_reuseport_cb))
1524 		reuseport_detach_sock(sk);
1525 
1526 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1527 
1528 	if (atomic_read(&sk->sk_omem_alloc))
1529 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1530 			 __func__, atomic_read(&sk->sk_omem_alloc));
1531 
1532 	if (sk->sk_frag.page) {
1533 		put_page(sk->sk_frag.page);
1534 		sk->sk_frag.page = NULL;
1535 	}
1536 
1537 	if (sk->sk_peer_cred)
1538 		put_cred(sk->sk_peer_cred);
1539 	put_pid(sk->sk_peer_pid);
1540 	if (likely(sk->sk_net_refcnt))
1541 		put_net(sock_net(sk));
1542 	sk_prot_free(sk->sk_prot_creator, sk);
1543 }
1544 
1545 void sk_destruct(struct sock *sk)
1546 {
1547 	if (sock_flag(sk, SOCK_RCU_FREE))
1548 		call_rcu(&sk->sk_rcu, __sk_destruct);
1549 	else
1550 		__sk_destruct(&sk->sk_rcu);
1551 }
1552 
1553 static void __sk_free(struct sock *sk)
1554 {
1555 	if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1556 		sock_diag_broadcast_destroy(sk);
1557 	else
1558 		sk_destruct(sk);
1559 }
1560 
1561 void sk_free(struct sock *sk)
1562 {
1563 	/*
1564 	 * We subtract one from sk_wmem_alloc and can know if
1565 	 * some packets are still in some tx queue.
1566 	 * If not null, sock_wfree() will call __sk_free(sk) later
1567 	 */
1568 	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1569 		__sk_free(sk);
1570 }
1571 EXPORT_SYMBOL(sk_free);
1572 
1573 static void sk_init_common(struct sock *sk)
1574 {
1575 	skb_queue_head_init(&sk->sk_receive_queue);
1576 	skb_queue_head_init(&sk->sk_write_queue);
1577 	skb_queue_head_init(&sk->sk_error_queue);
1578 
1579 	rwlock_init(&sk->sk_callback_lock);
1580 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1581 			af_rlock_keys + sk->sk_family,
1582 			af_family_rlock_key_strings[sk->sk_family]);
1583 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1584 			af_wlock_keys + sk->sk_family,
1585 			af_family_wlock_key_strings[sk->sk_family]);
1586 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1587 			af_elock_keys + sk->sk_family,
1588 			af_family_elock_key_strings[sk->sk_family]);
1589 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1590 			af_callback_keys + sk->sk_family,
1591 			af_family_clock_key_strings[sk->sk_family]);
1592 }
1593 
1594 /**
1595  *	sk_clone_lock - clone a socket, and lock its clone
1596  *	@sk: the socket to clone
1597  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1598  *
1599  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1600  */
1601 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1602 {
1603 	struct sock *newsk;
1604 	bool is_charged = true;
1605 
1606 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1607 	if (newsk != NULL) {
1608 		struct sk_filter *filter;
1609 
1610 		sock_copy(newsk, sk);
1611 
1612 		/* SANITY */
1613 		if (likely(newsk->sk_net_refcnt))
1614 			get_net(sock_net(newsk));
1615 		sk_node_init(&newsk->sk_node);
1616 		sock_lock_init(newsk);
1617 		bh_lock_sock(newsk);
1618 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1619 		newsk->sk_backlog.len = 0;
1620 
1621 		atomic_set(&newsk->sk_rmem_alloc, 0);
1622 		/*
1623 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1624 		 */
1625 		atomic_set(&newsk->sk_wmem_alloc, 1);
1626 		atomic_set(&newsk->sk_omem_alloc, 0);
1627 		sk_init_common(newsk);
1628 
1629 		newsk->sk_dst_cache	= NULL;
1630 		newsk->sk_dst_pending_confirm = 0;
1631 		newsk->sk_wmem_queued	= 0;
1632 		newsk->sk_forward_alloc = 0;
1633 		atomic_set(&newsk->sk_drops, 0);
1634 		newsk->sk_send_head	= NULL;
1635 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1636 
1637 		sock_reset_flag(newsk, SOCK_DONE);
1638 
1639 		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1640 		if (filter != NULL)
1641 			/* though it's an empty new sock, the charging may fail
1642 			 * if sysctl_optmem_max was changed between creation of
1643 			 * original socket and cloning
1644 			 */
1645 			is_charged = sk_filter_charge(newsk, filter);
1646 
1647 		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1648 			/* We need to make sure that we don't uncharge the new
1649 			 * socket if we couldn't charge it in the first place
1650 			 * as otherwise we uncharge the parent's filter.
1651 			 */
1652 			if (!is_charged)
1653 				RCU_INIT_POINTER(newsk->sk_filter, NULL);
1654 			sk_free_unlock_clone(newsk);
1655 			newsk = NULL;
1656 			goto out;
1657 		}
1658 		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1659 
1660 		newsk->sk_err	   = 0;
1661 		newsk->sk_err_soft = 0;
1662 		newsk->sk_priority = 0;
1663 		newsk->sk_incoming_cpu = raw_smp_processor_id();
1664 		atomic64_set(&newsk->sk_cookie, 0);
1665 
1666 		mem_cgroup_sk_alloc(newsk);
1667 		cgroup_sk_alloc(&newsk->sk_cgrp_data);
1668 
1669 		/*
1670 		 * Before updating sk_refcnt, we must commit prior changes to memory
1671 		 * (Documentation/RCU/rculist_nulls.txt for details)
1672 		 */
1673 		smp_wmb();
1674 		atomic_set(&newsk->sk_refcnt, 2);
1675 
1676 		/*
1677 		 * Increment the counter in the same struct proto as the master
1678 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1679 		 * is the same as sk->sk_prot->socks, as this field was copied
1680 		 * with memcpy).
1681 		 *
1682 		 * This _changes_ the previous behaviour, where
1683 		 * tcp_create_openreq_child always was incrementing the
1684 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1685 		 * to be taken into account in all callers. -acme
1686 		 */
1687 		sk_refcnt_debug_inc(newsk);
1688 		sk_set_socket(newsk, NULL);
1689 		newsk->sk_wq = NULL;
1690 
1691 		if (newsk->sk_prot->sockets_allocated)
1692 			sk_sockets_allocated_inc(newsk);
1693 
1694 		if (sock_needs_netstamp(sk) &&
1695 		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1696 			net_enable_timestamp();
1697 	}
1698 out:
1699 	return newsk;
1700 }
1701 EXPORT_SYMBOL_GPL(sk_clone_lock);
1702 
1703 void sk_free_unlock_clone(struct sock *sk)
1704 {
1705 	/* It is still raw copy of parent, so invalidate
1706 	 * destructor and make plain sk_free() */
1707 	sk->sk_destruct = NULL;
1708 	bh_unlock_sock(sk);
1709 	sk_free(sk);
1710 }
1711 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1712 
1713 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1714 {
1715 	u32 max_segs = 1;
1716 
1717 	sk_dst_set(sk, dst);
1718 	sk->sk_route_caps = dst->dev->features;
1719 	if (sk->sk_route_caps & NETIF_F_GSO)
1720 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1721 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1722 	if (sk_can_gso(sk)) {
1723 		if (dst->header_len) {
1724 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1725 		} else {
1726 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1727 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1728 			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1729 		}
1730 	}
1731 	sk->sk_gso_max_segs = max_segs;
1732 }
1733 EXPORT_SYMBOL_GPL(sk_setup_caps);
1734 
1735 /*
1736  *	Simple resource managers for sockets.
1737  */
1738 
1739 
1740 /*
1741  * Write buffer destructor automatically called from kfree_skb.
1742  */
1743 void sock_wfree(struct sk_buff *skb)
1744 {
1745 	struct sock *sk = skb->sk;
1746 	unsigned int len = skb->truesize;
1747 
1748 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1749 		/*
1750 		 * Keep a reference on sk_wmem_alloc, this will be released
1751 		 * after sk_write_space() call
1752 		 */
1753 		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1754 		sk->sk_write_space(sk);
1755 		len = 1;
1756 	}
1757 	/*
1758 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1759 	 * could not do because of in-flight packets
1760 	 */
1761 	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1762 		__sk_free(sk);
1763 }
1764 EXPORT_SYMBOL(sock_wfree);
1765 
1766 /* This variant of sock_wfree() is used by TCP,
1767  * since it sets SOCK_USE_WRITE_QUEUE.
1768  */
1769 void __sock_wfree(struct sk_buff *skb)
1770 {
1771 	struct sock *sk = skb->sk;
1772 
1773 	if (atomic_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1774 		__sk_free(sk);
1775 }
1776 
1777 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1778 {
1779 	skb_orphan(skb);
1780 	skb->sk = sk;
1781 #ifdef CONFIG_INET
1782 	if (unlikely(!sk_fullsock(sk))) {
1783 		skb->destructor = sock_edemux;
1784 		sock_hold(sk);
1785 		return;
1786 	}
1787 #endif
1788 	skb->destructor = sock_wfree;
1789 	skb_set_hash_from_sk(skb, sk);
1790 	/*
1791 	 * We used to take a refcount on sk, but following operation
1792 	 * is enough to guarantee sk_free() wont free this sock until
1793 	 * all in-flight packets are completed
1794 	 */
1795 	atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1796 }
1797 EXPORT_SYMBOL(skb_set_owner_w);
1798 
1799 /* This helper is used by netem, as it can hold packets in its
1800  * delay queue. We want to allow the owner socket to send more
1801  * packets, as if they were already TX completed by a typical driver.
1802  * But we also want to keep skb->sk set because some packet schedulers
1803  * rely on it (sch_fq for example).
1804  */
1805 void skb_orphan_partial(struct sk_buff *skb)
1806 {
1807 	if (skb_is_tcp_pure_ack(skb))
1808 		return;
1809 
1810 	if (skb->destructor == sock_wfree
1811 #ifdef CONFIG_INET
1812 	    || skb->destructor == tcp_wfree
1813 #endif
1814 		) {
1815 		struct sock *sk = skb->sk;
1816 
1817 		if (atomic_inc_not_zero(&sk->sk_refcnt)) {
1818 			atomic_sub(skb->truesize, &sk->sk_wmem_alloc);
1819 			skb->destructor = sock_efree;
1820 		}
1821 	} else {
1822 		skb_orphan(skb);
1823 	}
1824 }
1825 EXPORT_SYMBOL(skb_orphan_partial);
1826 
1827 /*
1828  * Read buffer destructor automatically called from kfree_skb.
1829  */
1830 void sock_rfree(struct sk_buff *skb)
1831 {
1832 	struct sock *sk = skb->sk;
1833 	unsigned int len = skb->truesize;
1834 
1835 	atomic_sub(len, &sk->sk_rmem_alloc);
1836 	sk_mem_uncharge(sk, len);
1837 }
1838 EXPORT_SYMBOL(sock_rfree);
1839 
1840 /*
1841  * Buffer destructor for skbs that are not used directly in read or write
1842  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1843  */
1844 void sock_efree(struct sk_buff *skb)
1845 {
1846 	sock_put(skb->sk);
1847 }
1848 EXPORT_SYMBOL(sock_efree);
1849 
1850 kuid_t sock_i_uid(struct sock *sk)
1851 {
1852 	kuid_t uid;
1853 
1854 	read_lock_bh(&sk->sk_callback_lock);
1855 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1856 	read_unlock_bh(&sk->sk_callback_lock);
1857 	return uid;
1858 }
1859 EXPORT_SYMBOL(sock_i_uid);
1860 
1861 unsigned long sock_i_ino(struct sock *sk)
1862 {
1863 	unsigned long ino;
1864 
1865 	read_lock_bh(&sk->sk_callback_lock);
1866 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1867 	read_unlock_bh(&sk->sk_callback_lock);
1868 	return ino;
1869 }
1870 EXPORT_SYMBOL(sock_i_ino);
1871 
1872 /*
1873  * Allocate a skb from the socket's send buffer.
1874  */
1875 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1876 			     gfp_t priority)
1877 {
1878 	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1879 		struct sk_buff *skb = alloc_skb(size, priority);
1880 		if (skb) {
1881 			skb_set_owner_w(skb, sk);
1882 			return skb;
1883 		}
1884 	}
1885 	return NULL;
1886 }
1887 EXPORT_SYMBOL(sock_wmalloc);
1888 
1889 /*
1890  * Allocate a memory block from the socket's option memory buffer.
1891  */
1892 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1893 {
1894 	if ((unsigned int)size <= sysctl_optmem_max &&
1895 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1896 		void *mem;
1897 		/* First do the add, to avoid the race if kmalloc
1898 		 * might sleep.
1899 		 */
1900 		atomic_add(size, &sk->sk_omem_alloc);
1901 		mem = kmalloc(size, priority);
1902 		if (mem)
1903 			return mem;
1904 		atomic_sub(size, &sk->sk_omem_alloc);
1905 	}
1906 	return NULL;
1907 }
1908 EXPORT_SYMBOL(sock_kmalloc);
1909 
1910 /* Free an option memory block. Note, we actually want the inline
1911  * here as this allows gcc to detect the nullify and fold away the
1912  * condition entirely.
1913  */
1914 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1915 				  const bool nullify)
1916 {
1917 	if (WARN_ON_ONCE(!mem))
1918 		return;
1919 	if (nullify)
1920 		kzfree(mem);
1921 	else
1922 		kfree(mem);
1923 	atomic_sub(size, &sk->sk_omem_alloc);
1924 }
1925 
1926 void sock_kfree_s(struct sock *sk, void *mem, int size)
1927 {
1928 	__sock_kfree_s(sk, mem, size, false);
1929 }
1930 EXPORT_SYMBOL(sock_kfree_s);
1931 
1932 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1933 {
1934 	__sock_kfree_s(sk, mem, size, true);
1935 }
1936 EXPORT_SYMBOL(sock_kzfree_s);
1937 
1938 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1939    I think, these locks should be removed for datagram sockets.
1940  */
1941 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1942 {
1943 	DEFINE_WAIT(wait);
1944 
1945 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1946 	for (;;) {
1947 		if (!timeo)
1948 			break;
1949 		if (signal_pending(current))
1950 			break;
1951 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1952 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1953 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1954 			break;
1955 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1956 			break;
1957 		if (sk->sk_err)
1958 			break;
1959 		timeo = schedule_timeout(timeo);
1960 	}
1961 	finish_wait(sk_sleep(sk), &wait);
1962 	return timeo;
1963 }
1964 
1965 
1966 /*
1967  *	Generic send/receive buffer handlers
1968  */
1969 
1970 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1971 				     unsigned long data_len, int noblock,
1972 				     int *errcode, int max_page_order)
1973 {
1974 	struct sk_buff *skb;
1975 	long timeo;
1976 	int err;
1977 
1978 	timeo = sock_sndtimeo(sk, noblock);
1979 	for (;;) {
1980 		err = sock_error(sk);
1981 		if (err != 0)
1982 			goto failure;
1983 
1984 		err = -EPIPE;
1985 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1986 			goto failure;
1987 
1988 		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1989 			break;
1990 
1991 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1992 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1993 		err = -EAGAIN;
1994 		if (!timeo)
1995 			goto failure;
1996 		if (signal_pending(current))
1997 			goto interrupted;
1998 		timeo = sock_wait_for_wmem(sk, timeo);
1999 	}
2000 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2001 				   errcode, sk->sk_allocation);
2002 	if (skb)
2003 		skb_set_owner_w(skb, sk);
2004 	return skb;
2005 
2006 interrupted:
2007 	err = sock_intr_errno(timeo);
2008 failure:
2009 	*errcode = err;
2010 	return NULL;
2011 }
2012 EXPORT_SYMBOL(sock_alloc_send_pskb);
2013 
2014 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2015 				    int noblock, int *errcode)
2016 {
2017 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2018 }
2019 EXPORT_SYMBOL(sock_alloc_send_skb);
2020 
2021 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2022 		     struct sockcm_cookie *sockc)
2023 {
2024 	u32 tsflags;
2025 
2026 	switch (cmsg->cmsg_type) {
2027 	case SO_MARK:
2028 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2029 			return -EPERM;
2030 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2031 			return -EINVAL;
2032 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2033 		break;
2034 	case SO_TIMESTAMPING:
2035 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2036 			return -EINVAL;
2037 
2038 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2039 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2040 			return -EINVAL;
2041 
2042 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2043 		sockc->tsflags |= tsflags;
2044 		break;
2045 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2046 	case SCM_RIGHTS:
2047 	case SCM_CREDENTIALS:
2048 		break;
2049 	default:
2050 		return -EINVAL;
2051 	}
2052 	return 0;
2053 }
2054 EXPORT_SYMBOL(__sock_cmsg_send);
2055 
2056 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2057 		   struct sockcm_cookie *sockc)
2058 {
2059 	struct cmsghdr *cmsg;
2060 	int ret;
2061 
2062 	for_each_cmsghdr(cmsg, msg) {
2063 		if (!CMSG_OK(msg, cmsg))
2064 			return -EINVAL;
2065 		if (cmsg->cmsg_level != SOL_SOCKET)
2066 			continue;
2067 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2068 		if (ret)
2069 			return ret;
2070 	}
2071 	return 0;
2072 }
2073 EXPORT_SYMBOL(sock_cmsg_send);
2074 
2075 /* On 32bit arches, an skb frag is limited to 2^15 */
2076 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2077 
2078 /**
2079  * skb_page_frag_refill - check that a page_frag contains enough room
2080  * @sz: minimum size of the fragment we want to get
2081  * @pfrag: pointer to page_frag
2082  * @gfp: priority for memory allocation
2083  *
2084  * Note: While this allocator tries to use high order pages, there is
2085  * no guarantee that allocations succeed. Therefore, @sz MUST be
2086  * less or equal than PAGE_SIZE.
2087  */
2088 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2089 {
2090 	if (pfrag->page) {
2091 		if (page_ref_count(pfrag->page) == 1) {
2092 			pfrag->offset = 0;
2093 			return true;
2094 		}
2095 		if (pfrag->offset + sz <= pfrag->size)
2096 			return true;
2097 		put_page(pfrag->page);
2098 	}
2099 
2100 	pfrag->offset = 0;
2101 	if (SKB_FRAG_PAGE_ORDER) {
2102 		/* Avoid direct reclaim but allow kswapd to wake */
2103 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2104 					  __GFP_COMP | __GFP_NOWARN |
2105 					  __GFP_NORETRY,
2106 					  SKB_FRAG_PAGE_ORDER);
2107 		if (likely(pfrag->page)) {
2108 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2109 			return true;
2110 		}
2111 	}
2112 	pfrag->page = alloc_page(gfp);
2113 	if (likely(pfrag->page)) {
2114 		pfrag->size = PAGE_SIZE;
2115 		return true;
2116 	}
2117 	return false;
2118 }
2119 EXPORT_SYMBOL(skb_page_frag_refill);
2120 
2121 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2122 {
2123 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2124 		return true;
2125 
2126 	sk_enter_memory_pressure(sk);
2127 	sk_stream_moderate_sndbuf(sk);
2128 	return false;
2129 }
2130 EXPORT_SYMBOL(sk_page_frag_refill);
2131 
2132 static void __lock_sock(struct sock *sk)
2133 	__releases(&sk->sk_lock.slock)
2134 	__acquires(&sk->sk_lock.slock)
2135 {
2136 	DEFINE_WAIT(wait);
2137 
2138 	for (;;) {
2139 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2140 					TASK_UNINTERRUPTIBLE);
2141 		spin_unlock_bh(&sk->sk_lock.slock);
2142 		schedule();
2143 		spin_lock_bh(&sk->sk_lock.slock);
2144 		if (!sock_owned_by_user(sk))
2145 			break;
2146 	}
2147 	finish_wait(&sk->sk_lock.wq, &wait);
2148 }
2149 
2150 static void __release_sock(struct sock *sk)
2151 	__releases(&sk->sk_lock.slock)
2152 	__acquires(&sk->sk_lock.slock)
2153 {
2154 	struct sk_buff *skb, *next;
2155 
2156 	while ((skb = sk->sk_backlog.head) != NULL) {
2157 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2158 
2159 		spin_unlock_bh(&sk->sk_lock.slock);
2160 
2161 		do {
2162 			next = skb->next;
2163 			prefetch(next);
2164 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2165 			skb->next = NULL;
2166 			sk_backlog_rcv(sk, skb);
2167 
2168 			cond_resched();
2169 
2170 			skb = next;
2171 		} while (skb != NULL);
2172 
2173 		spin_lock_bh(&sk->sk_lock.slock);
2174 	}
2175 
2176 	/*
2177 	 * Doing the zeroing here guarantee we can not loop forever
2178 	 * while a wild producer attempts to flood us.
2179 	 */
2180 	sk->sk_backlog.len = 0;
2181 }
2182 
2183 void __sk_flush_backlog(struct sock *sk)
2184 {
2185 	spin_lock_bh(&sk->sk_lock.slock);
2186 	__release_sock(sk);
2187 	spin_unlock_bh(&sk->sk_lock.slock);
2188 }
2189 
2190 /**
2191  * sk_wait_data - wait for data to arrive at sk_receive_queue
2192  * @sk:    sock to wait on
2193  * @timeo: for how long
2194  * @skb:   last skb seen on sk_receive_queue
2195  *
2196  * Now socket state including sk->sk_err is changed only under lock,
2197  * hence we may omit checks after joining wait queue.
2198  * We check receive queue before schedule() only as optimization;
2199  * it is very likely that release_sock() added new data.
2200  */
2201 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2202 {
2203 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2204 	int rc;
2205 
2206 	add_wait_queue(sk_sleep(sk), &wait);
2207 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2208 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2209 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2210 	remove_wait_queue(sk_sleep(sk), &wait);
2211 	return rc;
2212 }
2213 EXPORT_SYMBOL(sk_wait_data);
2214 
2215 /**
2216  *	__sk_mem_raise_allocated - increase memory_allocated
2217  *	@sk: socket
2218  *	@size: memory size to allocate
2219  *	@amt: pages to allocate
2220  *	@kind: allocation type
2221  *
2222  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2223  */
2224 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2225 {
2226 	struct proto *prot = sk->sk_prot;
2227 	long allocated = sk_memory_allocated_add(sk, amt);
2228 
2229 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2230 	    !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2231 		goto suppress_allocation;
2232 
2233 	/* Under limit. */
2234 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2235 		sk_leave_memory_pressure(sk);
2236 		return 1;
2237 	}
2238 
2239 	/* Under pressure. */
2240 	if (allocated > sk_prot_mem_limits(sk, 1))
2241 		sk_enter_memory_pressure(sk);
2242 
2243 	/* Over hard limit. */
2244 	if (allocated > sk_prot_mem_limits(sk, 2))
2245 		goto suppress_allocation;
2246 
2247 	/* guarantee minimum buffer size under pressure */
2248 	if (kind == SK_MEM_RECV) {
2249 		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2250 			return 1;
2251 
2252 	} else { /* SK_MEM_SEND */
2253 		if (sk->sk_type == SOCK_STREAM) {
2254 			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2255 				return 1;
2256 		} else if (atomic_read(&sk->sk_wmem_alloc) <
2257 			   prot->sysctl_wmem[0])
2258 				return 1;
2259 	}
2260 
2261 	if (sk_has_memory_pressure(sk)) {
2262 		int alloc;
2263 
2264 		if (!sk_under_memory_pressure(sk))
2265 			return 1;
2266 		alloc = sk_sockets_allocated_read_positive(sk);
2267 		if (sk_prot_mem_limits(sk, 2) > alloc *
2268 		    sk_mem_pages(sk->sk_wmem_queued +
2269 				 atomic_read(&sk->sk_rmem_alloc) +
2270 				 sk->sk_forward_alloc))
2271 			return 1;
2272 	}
2273 
2274 suppress_allocation:
2275 
2276 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2277 		sk_stream_moderate_sndbuf(sk);
2278 
2279 		/* Fail only if socket is _under_ its sndbuf.
2280 		 * In this case we cannot block, so that we have to fail.
2281 		 */
2282 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2283 			return 1;
2284 	}
2285 
2286 	trace_sock_exceed_buf_limit(sk, prot, allocated);
2287 
2288 	sk_memory_allocated_sub(sk, amt);
2289 
2290 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2291 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2292 
2293 	return 0;
2294 }
2295 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2296 
2297 /**
2298  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2299  *	@sk: socket
2300  *	@size: memory size to allocate
2301  *	@kind: allocation type
2302  *
2303  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2304  *	rmem allocation. This function assumes that protocols which have
2305  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2306  */
2307 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2308 {
2309 	int ret, amt = sk_mem_pages(size);
2310 
2311 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2312 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2313 	if (!ret)
2314 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2315 	return ret;
2316 }
2317 EXPORT_SYMBOL(__sk_mem_schedule);
2318 
2319 /**
2320  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2321  *	@sk: socket
2322  *	@amount: number of quanta
2323  *
2324  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2325  */
2326 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2327 {
2328 	sk_memory_allocated_sub(sk, amount);
2329 
2330 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2331 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2332 
2333 	if (sk_under_memory_pressure(sk) &&
2334 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2335 		sk_leave_memory_pressure(sk);
2336 }
2337 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2338 
2339 /**
2340  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2341  *	@sk: socket
2342  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2343  */
2344 void __sk_mem_reclaim(struct sock *sk, int amount)
2345 {
2346 	amount >>= SK_MEM_QUANTUM_SHIFT;
2347 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2348 	__sk_mem_reduce_allocated(sk, amount);
2349 }
2350 EXPORT_SYMBOL(__sk_mem_reclaim);
2351 
2352 int sk_set_peek_off(struct sock *sk, int val)
2353 {
2354 	if (val < 0)
2355 		return -EINVAL;
2356 
2357 	sk->sk_peek_off = val;
2358 	return 0;
2359 }
2360 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2361 
2362 /*
2363  * Set of default routines for initialising struct proto_ops when
2364  * the protocol does not support a particular function. In certain
2365  * cases where it makes no sense for a protocol to have a "do nothing"
2366  * function, some default processing is provided.
2367  */
2368 
2369 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2370 {
2371 	return -EOPNOTSUPP;
2372 }
2373 EXPORT_SYMBOL(sock_no_bind);
2374 
2375 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2376 		    int len, int flags)
2377 {
2378 	return -EOPNOTSUPP;
2379 }
2380 EXPORT_SYMBOL(sock_no_connect);
2381 
2382 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2383 {
2384 	return -EOPNOTSUPP;
2385 }
2386 EXPORT_SYMBOL(sock_no_socketpair);
2387 
2388 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2389 		   bool kern)
2390 {
2391 	return -EOPNOTSUPP;
2392 }
2393 EXPORT_SYMBOL(sock_no_accept);
2394 
2395 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2396 		    int *len, int peer)
2397 {
2398 	return -EOPNOTSUPP;
2399 }
2400 EXPORT_SYMBOL(sock_no_getname);
2401 
2402 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2403 {
2404 	return 0;
2405 }
2406 EXPORT_SYMBOL(sock_no_poll);
2407 
2408 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2409 {
2410 	return -EOPNOTSUPP;
2411 }
2412 EXPORT_SYMBOL(sock_no_ioctl);
2413 
2414 int sock_no_listen(struct socket *sock, int backlog)
2415 {
2416 	return -EOPNOTSUPP;
2417 }
2418 EXPORT_SYMBOL(sock_no_listen);
2419 
2420 int sock_no_shutdown(struct socket *sock, int how)
2421 {
2422 	return -EOPNOTSUPP;
2423 }
2424 EXPORT_SYMBOL(sock_no_shutdown);
2425 
2426 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2427 		    char __user *optval, unsigned int optlen)
2428 {
2429 	return -EOPNOTSUPP;
2430 }
2431 EXPORT_SYMBOL(sock_no_setsockopt);
2432 
2433 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2434 		    char __user *optval, int __user *optlen)
2435 {
2436 	return -EOPNOTSUPP;
2437 }
2438 EXPORT_SYMBOL(sock_no_getsockopt);
2439 
2440 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2441 {
2442 	return -EOPNOTSUPP;
2443 }
2444 EXPORT_SYMBOL(sock_no_sendmsg);
2445 
2446 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2447 		    int flags)
2448 {
2449 	return -EOPNOTSUPP;
2450 }
2451 EXPORT_SYMBOL(sock_no_recvmsg);
2452 
2453 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2454 {
2455 	/* Mirror missing mmap method error code */
2456 	return -ENODEV;
2457 }
2458 EXPORT_SYMBOL(sock_no_mmap);
2459 
2460 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2461 {
2462 	ssize_t res;
2463 	struct msghdr msg = {.msg_flags = flags};
2464 	struct kvec iov;
2465 	char *kaddr = kmap(page);
2466 	iov.iov_base = kaddr + offset;
2467 	iov.iov_len = size;
2468 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2469 	kunmap(page);
2470 	return res;
2471 }
2472 EXPORT_SYMBOL(sock_no_sendpage);
2473 
2474 /*
2475  *	Default Socket Callbacks
2476  */
2477 
2478 static void sock_def_wakeup(struct sock *sk)
2479 {
2480 	struct socket_wq *wq;
2481 
2482 	rcu_read_lock();
2483 	wq = rcu_dereference(sk->sk_wq);
2484 	if (skwq_has_sleeper(wq))
2485 		wake_up_interruptible_all(&wq->wait);
2486 	rcu_read_unlock();
2487 }
2488 
2489 static void sock_def_error_report(struct sock *sk)
2490 {
2491 	struct socket_wq *wq;
2492 
2493 	rcu_read_lock();
2494 	wq = rcu_dereference(sk->sk_wq);
2495 	if (skwq_has_sleeper(wq))
2496 		wake_up_interruptible_poll(&wq->wait, POLLERR);
2497 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2498 	rcu_read_unlock();
2499 }
2500 
2501 static void sock_def_readable(struct sock *sk)
2502 {
2503 	struct socket_wq *wq;
2504 
2505 	rcu_read_lock();
2506 	wq = rcu_dereference(sk->sk_wq);
2507 	if (skwq_has_sleeper(wq))
2508 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2509 						POLLRDNORM | POLLRDBAND);
2510 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2511 	rcu_read_unlock();
2512 }
2513 
2514 static void sock_def_write_space(struct sock *sk)
2515 {
2516 	struct socket_wq *wq;
2517 
2518 	rcu_read_lock();
2519 
2520 	/* Do not wake up a writer until he can make "significant"
2521 	 * progress.  --DaveM
2522 	 */
2523 	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2524 		wq = rcu_dereference(sk->sk_wq);
2525 		if (skwq_has_sleeper(wq))
2526 			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2527 						POLLWRNORM | POLLWRBAND);
2528 
2529 		/* Should agree with poll, otherwise some programs break */
2530 		if (sock_writeable(sk))
2531 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2532 	}
2533 
2534 	rcu_read_unlock();
2535 }
2536 
2537 static void sock_def_destruct(struct sock *sk)
2538 {
2539 }
2540 
2541 void sk_send_sigurg(struct sock *sk)
2542 {
2543 	if (sk->sk_socket && sk->sk_socket->file)
2544 		if (send_sigurg(&sk->sk_socket->file->f_owner))
2545 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2546 }
2547 EXPORT_SYMBOL(sk_send_sigurg);
2548 
2549 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2550 		    unsigned long expires)
2551 {
2552 	if (!mod_timer(timer, expires))
2553 		sock_hold(sk);
2554 }
2555 EXPORT_SYMBOL(sk_reset_timer);
2556 
2557 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2558 {
2559 	if (del_timer(timer))
2560 		__sock_put(sk);
2561 }
2562 EXPORT_SYMBOL(sk_stop_timer);
2563 
2564 void sock_init_data(struct socket *sock, struct sock *sk)
2565 {
2566 	sk_init_common(sk);
2567 	sk->sk_send_head	=	NULL;
2568 
2569 	init_timer(&sk->sk_timer);
2570 
2571 	sk->sk_allocation	=	GFP_KERNEL;
2572 	sk->sk_rcvbuf		=	sysctl_rmem_default;
2573 	sk->sk_sndbuf		=	sysctl_wmem_default;
2574 	sk->sk_state		=	TCP_CLOSE;
2575 	sk_set_socket(sk, sock);
2576 
2577 	sock_set_flag(sk, SOCK_ZAPPED);
2578 
2579 	if (sock) {
2580 		sk->sk_type	=	sock->type;
2581 		sk->sk_wq	=	sock->wq;
2582 		sock->sk	=	sk;
2583 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2584 	} else {
2585 		sk->sk_wq	=	NULL;
2586 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2587 	}
2588 
2589 	rwlock_init(&sk->sk_callback_lock);
2590 	if (sk->sk_kern_sock)
2591 		lockdep_set_class_and_name(
2592 			&sk->sk_callback_lock,
2593 			af_kern_callback_keys + sk->sk_family,
2594 			af_family_kern_clock_key_strings[sk->sk_family]);
2595 	else
2596 		lockdep_set_class_and_name(
2597 			&sk->sk_callback_lock,
2598 			af_callback_keys + sk->sk_family,
2599 			af_family_clock_key_strings[sk->sk_family]);
2600 
2601 	sk->sk_state_change	=	sock_def_wakeup;
2602 	sk->sk_data_ready	=	sock_def_readable;
2603 	sk->sk_write_space	=	sock_def_write_space;
2604 	sk->sk_error_report	=	sock_def_error_report;
2605 	sk->sk_destruct		=	sock_def_destruct;
2606 
2607 	sk->sk_frag.page	=	NULL;
2608 	sk->sk_frag.offset	=	0;
2609 	sk->sk_peek_off		=	-1;
2610 
2611 	sk->sk_peer_pid 	=	NULL;
2612 	sk->sk_peer_cred	=	NULL;
2613 	sk->sk_write_pending	=	0;
2614 	sk->sk_rcvlowat		=	1;
2615 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2616 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2617 
2618 	sk->sk_stamp = SK_DEFAULT_STAMP;
2619 
2620 #ifdef CONFIG_NET_RX_BUSY_POLL
2621 	sk->sk_napi_id		=	0;
2622 	sk->sk_ll_usec		=	sysctl_net_busy_read;
2623 #endif
2624 
2625 	sk->sk_max_pacing_rate = ~0U;
2626 	sk->sk_pacing_rate = ~0U;
2627 	sk->sk_incoming_cpu = -1;
2628 	/*
2629 	 * Before updating sk_refcnt, we must commit prior changes to memory
2630 	 * (Documentation/RCU/rculist_nulls.txt for details)
2631 	 */
2632 	smp_wmb();
2633 	atomic_set(&sk->sk_refcnt, 1);
2634 	atomic_set(&sk->sk_drops, 0);
2635 }
2636 EXPORT_SYMBOL(sock_init_data);
2637 
2638 void lock_sock_nested(struct sock *sk, int subclass)
2639 {
2640 	might_sleep();
2641 	spin_lock_bh(&sk->sk_lock.slock);
2642 	if (sk->sk_lock.owned)
2643 		__lock_sock(sk);
2644 	sk->sk_lock.owned = 1;
2645 	spin_unlock(&sk->sk_lock.slock);
2646 	/*
2647 	 * The sk_lock has mutex_lock() semantics here:
2648 	 */
2649 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2650 	local_bh_enable();
2651 }
2652 EXPORT_SYMBOL(lock_sock_nested);
2653 
2654 void release_sock(struct sock *sk)
2655 {
2656 	spin_lock_bh(&sk->sk_lock.slock);
2657 	if (sk->sk_backlog.tail)
2658 		__release_sock(sk);
2659 
2660 	/* Warning : release_cb() might need to release sk ownership,
2661 	 * ie call sock_release_ownership(sk) before us.
2662 	 */
2663 	if (sk->sk_prot->release_cb)
2664 		sk->sk_prot->release_cb(sk);
2665 
2666 	sock_release_ownership(sk);
2667 	if (waitqueue_active(&sk->sk_lock.wq))
2668 		wake_up(&sk->sk_lock.wq);
2669 	spin_unlock_bh(&sk->sk_lock.slock);
2670 }
2671 EXPORT_SYMBOL(release_sock);
2672 
2673 /**
2674  * lock_sock_fast - fast version of lock_sock
2675  * @sk: socket
2676  *
2677  * This version should be used for very small section, where process wont block
2678  * return false if fast path is taken
2679  *   sk_lock.slock locked, owned = 0, BH disabled
2680  * return true if slow path is taken
2681  *   sk_lock.slock unlocked, owned = 1, BH enabled
2682  */
2683 bool lock_sock_fast(struct sock *sk)
2684 {
2685 	might_sleep();
2686 	spin_lock_bh(&sk->sk_lock.slock);
2687 
2688 	if (!sk->sk_lock.owned)
2689 		/*
2690 		 * Note : We must disable BH
2691 		 */
2692 		return false;
2693 
2694 	__lock_sock(sk);
2695 	sk->sk_lock.owned = 1;
2696 	spin_unlock(&sk->sk_lock.slock);
2697 	/*
2698 	 * The sk_lock has mutex_lock() semantics here:
2699 	 */
2700 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2701 	local_bh_enable();
2702 	return true;
2703 }
2704 EXPORT_SYMBOL(lock_sock_fast);
2705 
2706 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2707 {
2708 	struct timeval tv;
2709 	if (!sock_flag(sk, SOCK_TIMESTAMP))
2710 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2711 	tv = ktime_to_timeval(sk->sk_stamp);
2712 	if (tv.tv_sec == -1)
2713 		return -ENOENT;
2714 	if (tv.tv_sec == 0) {
2715 		sk->sk_stamp = ktime_get_real();
2716 		tv = ktime_to_timeval(sk->sk_stamp);
2717 	}
2718 	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2719 }
2720 EXPORT_SYMBOL(sock_get_timestamp);
2721 
2722 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2723 {
2724 	struct timespec ts;
2725 	if (!sock_flag(sk, SOCK_TIMESTAMP))
2726 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2727 	ts = ktime_to_timespec(sk->sk_stamp);
2728 	if (ts.tv_sec == -1)
2729 		return -ENOENT;
2730 	if (ts.tv_sec == 0) {
2731 		sk->sk_stamp = ktime_get_real();
2732 		ts = ktime_to_timespec(sk->sk_stamp);
2733 	}
2734 	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2735 }
2736 EXPORT_SYMBOL(sock_get_timestampns);
2737 
2738 void sock_enable_timestamp(struct sock *sk, int flag)
2739 {
2740 	if (!sock_flag(sk, flag)) {
2741 		unsigned long previous_flags = sk->sk_flags;
2742 
2743 		sock_set_flag(sk, flag);
2744 		/*
2745 		 * we just set one of the two flags which require net
2746 		 * time stamping, but time stamping might have been on
2747 		 * already because of the other one
2748 		 */
2749 		if (sock_needs_netstamp(sk) &&
2750 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
2751 			net_enable_timestamp();
2752 	}
2753 }
2754 
2755 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2756 		       int level, int type)
2757 {
2758 	struct sock_exterr_skb *serr;
2759 	struct sk_buff *skb;
2760 	int copied, err;
2761 
2762 	err = -EAGAIN;
2763 	skb = sock_dequeue_err_skb(sk);
2764 	if (skb == NULL)
2765 		goto out;
2766 
2767 	copied = skb->len;
2768 	if (copied > len) {
2769 		msg->msg_flags |= MSG_TRUNC;
2770 		copied = len;
2771 	}
2772 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
2773 	if (err)
2774 		goto out_free_skb;
2775 
2776 	sock_recv_timestamp(msg, sk, skb);
2777 
2778 	serr = SKB_EXT_ERR(skb);
2779 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2780 
2781 	msg->msg_flags |= MSG_ERRQUEUE;
2782 	err = copied;
2783 
2784 out_free_skb:
2785 	kfree_skb(skb);
2786 out:
2787 	return err;
2788 }
2789 EXPORT_SYMBOL(sock_recv_errqueue);
2790 
2791 /*
2792  *	Get a socket option on an socket.
2793  *
2794  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2795  *	asynchronous errors should be reported by getsockopt. We assume
2796  *	this means if you specify SO_ERROR (otherwise whats the point of it).
2797  */
2798 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2799 			   char __user *optval, int __user *optlen)
2800 {
2801 	struct sock *sk = sock->sk;
2802 
2803 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2804 }
2805 EXPORT_SYMBOL(sock_common_getsockopt);
2806 
2807 #ifdef CONFIG_COMPAT
2808 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2809 				  char __user *optval, int __user *optlen)
2810 {
2811 	struct sock *sk = sock->sk;
2812 
2813 	if (sk->sk_prot->compat_getsockopt != NULL)
2814 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2815 						      optval, optlen);
2816 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2817 }
2818 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2819 #endif
2820 
2821 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2822 			int flags)
2823 {
2824 	struct sock *sk = sock->sk;
2825 	int addr_len = 0;
2826 	int err;
2827 
2828 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2829 				   flags & ~MSG_DONTWAIT, &addr_len);
2830 	if (err >= 0)
2831 		msg->msg_namelen = addr_len;
2832 	return err;
2833 }
2834 EXPORT_SYMBOL(sock_common_recvmsg);
2835 
2836 /*
2837  *	Set socket options on an inet socket.
2838  */
2839 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2840 			   char __user *optval, unsigned int optlen)
2841 {
2842 	struct sock *sk = sock->sk;
2843 
2844 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2845 }
2846 EXPORT_SYMBOL(sock_common_setsockopt);
2847 
2848 #ifdef CONFIG_COMPAT
2849 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2850 				  char __user *optval, unsigned int optlen)
2851 {
2852 	struct sock *sk = sock->sk;
2853 
2854 	if (sk->sk_prot->compat_setsockopt != NULL)
2855 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2856 						      optval, optlen);
2857 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2858 }
2859 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2860 #endif
2861 
2862 void sk_common_release(struct sock *sk)
2863 {
2864 	if (sk->sk_prot->destroy)
2865 		sk->sk_prot->destroy(sk);
2866 
2867 	/*
2868 	 * Observation: when sock_common_release is called, processes have
2869 	 * no access to socket. But net still has.
2870 	 * Step one, detach it from networking:
2871 	 *
2872 	 * A. Remove from hash tables.
2873 	 */
2874 
2875 	sk->sk_prot->unhash(sk);
2876 
2877 	/*
2878 	 * In this point socket cannot receive new packets, but it is possible
2879 	 * that some packets are in flight because some CPU runs receiver and
2880 	 * did hash table lookup before we unhashed socket. They will achieve
2881 	 * receive queue and will be purged by socket destructor.
2882 	 *
2883 	 * Also we still have packets pending on receive queue and probably,
2884 	 * our own packets waiting in device queues. sock_destroy will drain
2885 	 * receive queue, but transmitted packets will delay socket destruction
2886 	 * until the last reference will be released.
2887 	 */
2888 
2889 	sock_orphan(sk);
2890 
2891 	xfrm_sk_free_policy(sk);
2892 
2893 	sk_refcnt_debug_release(sk);
2894 
2895 	sock_put(sk);
2896 }
2897 EXPORT_SYMBOL(sk_common_release);
2898 
2899 void sk_get_meminfo(const struct sock *sk, u32 *mem)
2900 {
2901 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
2902 
2903 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
2904 	mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
2905 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
2906 	mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
2907 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
2908 	mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
2909 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
2910 	mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
2911 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
2912 }
2913 
2914 #ifdef CONFIG_PROC_FS
2915 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
2916 struct prot_inuse {
2917 	int val[PROTO_INUSE_NR];
2918 };
2919 
2920 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2921 
2922 #ifdef CONFIG_NET_NS
2923 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2924 {
2925 	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2926 }
2927 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2928 
2929 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2930 {
2931 	int cpu, idx = prot->inuse_idx;
2932 	int res = 0;
2933 
2934 	for_each_possible_cpu(cpu)
2935 		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2936 
2937 	return res >= 0 ? res : 0;
2938 }
2939 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2940 
2941 static int __net_init sock_inuse_init_net(struct net *net)
2942 {
2943 	net->core.inuse = alloc_percpu(struct prot_inuse);
2944 	return net->core.inuse ? 0 : -ENOMEM;
2945 }
2946 
2947 static void __net_exit sock_inuse_exit_net(struct net *net)
2948 {
2949 	free_percpu(net->core.inuse);
2950 }
2951 
2952 static struct pernet_operations net_inuse_ops = {
2953 	.init = sock_inuse_init_net,
2954 	.exit = sock_inuse_exit_net,
2955 };
2956 
2957 static __init int net_inuse_init(void)
2958 {
2959 	if (register_pernet_subsys(&net_inuse_ops))
2960 		panic("Cannot initialize net inuse counters");
2961 
2962 	return 0;
2963 }
2964 
2965 core_initcall(net_inuse_init);
2966 #else
2967 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2968 
2969 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2970 {
2971 	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2972 }
2973 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2974 
2975 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2976 {
2977 	int cpu, idx = prot->inuse_idx;
2978 	int res = 0;
2979 
2980 	for_each_possible_cpu(cpu)
2981 		res += per_cpu(prot_inuse, cpu).val[idx];
2982 
2983 	return res >= 0 ? res : 0;
2984 }
2985 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2986 #endif
2987 
2988 static void assign_proto_idx(struct proto *prot)
2989 {
2990 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2991 
2992 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2993 		pr_err("PROTO_INUSE_NR exhausted\n");
2994 		return;
2995 	}
2996 
2997 	set_bit(prot->inuse_idx, proto_inuse_idx);
2998 }
2999 
3000 static void release_proto_idx(struct proto *prot)
3001 {
3002 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3003 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3004 }
3005 #else
3006 static inline void assign_proto_idx(struct proto *prot)
3007 {
3008 }
3009 
3010 static inline void release_proto_idx(struct proto *prot)
3011 {
3012 }
3013 #endif
3014 
3015 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3016 {
3017 	if (!rsk_prot)
3018 		return;
3019 	kfree(rsk_prot->slab_name);
3020 	rsk_prot->slab_name = NULL;
3021 	kmem_cache_destroy(rsk_prot->slab);
3022 	rsk_prot->slab = NULL;
3023 }
3024 
3025 static int req_prot_init(const struct proto *prot)
3026 {
3027 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3028 
3029 	if (!rsk_prot)
3030 		return 0;
3031 
3032 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3033 					prot->name);
3034 	if (!rsk_prot->slab_name)
3035 		return -ENOMEM;
3036 
3037 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3038 					   rsk_prot->obj_size, 0,
3039 					   prot->slab_flags, NULL);
3040 
3041 	if (!rsk_prot->slab) {
3042 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3043 			prot->name);
3044 		return -ENOMEM;
3045 	}
3046 	return 0;
3047 }
3048 
3049 int proto_register(struct proto *prot, int alloc_slab)
3050 {
3051 	if (alloc_slab) {
3052 		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
3053 					SLAB_HWCACHE_ALIGN | prot->slab_flags,
3054 					NULL);
3055 
3056 		if (prot->slab == NULL) {
3057 			pr_crit("%s: Can't create sock SLAB cache!\n",
3058 				prot->name);
3059 			goto out;
3060 		}
3061 
3062 		if (req_prot_init(prot))
3063 			goto out_free_request_sock_slab;
3064 
3065 		if (prot->twsk_prot != NULL) {
3066 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3067 
3068 			if (prot->twsk_prot->twsk_slab_name == NULL)
3069 				goto out_free_request_sock_slab;
3070 
3071 			prot->twsk_prot->twsk_slab =
3072 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3073 						  prot->twsk_prot->twsk_obj_size,
3074 						  0,
3075 						  prot->slab_flags,
3076 						  NULL);
3077 			if (prot->twsk_prot->twsk_slab == NULL)
3078 				goto out_free_timewait_sock_slab_name;
3079 		}
3080 	}
3081 
3082 	mutex_lock(&proto_list_mutex);
3083 	list_add(&prot->node, &proto_list);
3084 	assign_proto_idx(prot);
3085 	mutex_unlock(&proto_list_mutex);
3086 	return 0;
3087 
3088 out_free_timewait_sock_slab_name:
3089 	kfree(prot->twsk_prot->twsk_slab_name);
3090 out_free_request_sock_slab:
3091 	req_prot_cleanup(prot->rsk_prot);
3092 
3093 	kmem_cache_destroy(prot->slab);
3094 	prot->slab = NULL;
3095 out:
3096 	return -ENOBUFS;
3097 }
3098 EXPORT_SYMBOL(proto_register);
3099 
3100 void proto_unregister(struct proto *prot)
3101 {
3102 	mutex_lock(&proto_list_mutex);
3103 	release_proto_idx(prot);
3104 	list_del(&prot->node);
3105 	mutex_unlock(&proto_list_mutex);
3106 
3107 	kmem_cache_destroy(prot->slab);
3108 	prot->slab = NULL;
3109 
3110 	req_prot_cleanup(prot->rsk_prot);
3111 
3112 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3113 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3114 		kfree(prot->twsk_prot->twsk_slab_name);
3115 		prot->twsk_prot->twsk_slab = NULL;
3116 	}
3117 }
3118 EXPORT_SYMBOL(proto_unregister);
3119 
3120 #ifdef CONFIG_PROC_FS
3121 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3122 	__acquires(proto_list_mutex)
3123 {
3124 	mutex_lock(&proto_list_mutex);
3125 	return seq_list_start_head(&proto_list, *pos);
3126 }
3127 
3128 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3129 {
3130 	return seq_list_next(v, &proto_list, pos);
3131 }
3132 
3133 static void proto_seq_stop(struct seq_file *seq, void *v)
3134 	__releases(proto_list_mutex)
3135 {
3136 	mutex_unlock(&proto_list_mutex);
3137 }
3138 
3139 static char proto_method_implemented(const void *method)
3140 {
3141 	return method == NULL ? 'n' : 'y';
3142 }
3143 static long sock_prot_memory_allocated(struct proto *proto)
3144 {
3145 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3146 }
3147 
3148 static char *sock_prot_memory_pressure(struct proto *proto)
3149 {
3150 	return proto->memory_pressure != NULL ?
3151 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3152 }
3153 
3154 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3155 {
3156 
3157 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3158 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3159 		   proto->name,
3160 		   proto->obj_size,
3161 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3162 		   sock_prot_memory_allocated(proto),
3163 		   sock_prot_memory_pressure(proto),
3164 		   proto->max_header,
3165 		   proto->slab == NULL ? "no" : "yes",
3166 		   module_name(proto->owner),
3167 		   proto_method_implemented(proto->close),
3168 		   proto_method_implemented(proto->connect),
3169 		   proto_method_implemented(proto->disconnect),
3170 		   proto_method_implemented(proto->accept),
3171 		   proto_method_implemented(proto->ioctl),
3172 		   proto_method_implemented(proto->init),
3173 		   proto_method_implemented(proto->destroy),
3174 		   proto_method_implemented(proto->shutdown),
3175 		   proto_method_implemented(proto->setsockopt),
3176 		   proto_method_implemented(proto->getsockopt),
3177 		   proto_method_implemented(proto->sendmsg),
3178 		   proto_method_implemented(proto->recvmsg),
3179 		   proto_method_implemented(proto->sendpage),
3180 		   proto_method_implemented(proto->bind),
3181 		   proto_method_implemented(proto->backlog_rcv),
3182 		   proto_method_implemented(proto->hash),
3183 		   proto_method_implemented(proto->unhash),
3184 		   proto_method_implemented(proto->get_port),
3185 		   proto_method_implemented(proto->enter_memory_pressure));
3186 }
3187 
3188 static int proto_seq_show(struct seq_file *seq, void *v)
3189 {
3190 	if (v == &proto_list)
3191 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3192 			   "protocol",
3193 			   "size",
3194 			   "sockets",
3195 			   "memory",
3196 			   "press",
3197 			   "maxhdr",
3198 			   "slab",
3199 			   "module",
3200 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3201 	else
3202 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3203 	return 0;
3204 }
3205 
3206 static const struct seq_operations proto_seq_ops = {
3207 	.start  = proto_seq_start,
3208 	.next   = proto_seq_next,
3209 	.stop   = proto_seq_stop,
3210 	.show   = proto_seq_show,
3211 };
3212 
3213 static int proto_seq_open(struct inode *inode, struct file *file)
3214 {
3215 	return seq_open_net(inode, file, &proto_seq_ops,
3216 			    sizeof(struct seq_net_private));
3217 }
3218 
3219 static const struct file_operations proto_seq_fops = {
3220 	.owner		= THIS_MODULE,
3221 	.open		= proto_seq_open,
3222 	.read		= seq_read,
3223 	.llseek		= seq_lseek,
3224 	.release	= seq_release_net,
3225 };
3226 
3227 static __net_init int proto_init_net(struct net *net)
3228 {
3229 	if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3230 		return -ENOMEM;
3231 
3232 	return 0;
3233 }
3234 
3235 static __net_exit void proto_exit_net(struct net *net)
3236 {
3237 	remove_proc_entry("protocols", net->proc_net);
3238 }
3239 
3240 
3241 static __net_initdata struct pernet_operations proto_net_ops = {
3242 	.init = proto_init_net,
3243 	.exit = proto_exit_net,
3244 };
3245 
3246 static int __init proto_init(void)
3247 {
3248 	return register_pernet_subsys(&proto_net_ops);
3249 }
3250 
3251 subsys_initcall(proto_init);
3252 
3253 #endif /* PROC_FS */
3254 
3255 #ifdef CONFIG_NET_RX_BUSY_POLL
3256 bool sk_busy_loop_end(void *p, unsigned long start_time)
3257 {
3258 	struct sock *sk = p;
3259 
3260 	return !skb_queue_empty(&sk->sk_receive_queue) ||
3261 	       sk_busy_loop_timeout(sk, start_time);
3262 }
3263 EXPORT_SYMBOL(sk_busy_loop_end);
3264 #endif /* CONFIG_NET_RX_BUSY_POLL */
3265